def extract_key_performance_indicators(data):
    """
    Extract key performance indicators from a list of tuples.

    Args:
        data (list): List of tuples containing v5_id, value, and other metrics.

    Returns:
        dict: Dictionary with v5_id as keys and corresponding values.
    """
    return {item[0]: item[1] for item in data}

# Example usage
data = [('v5_1768236144', 108217.11959687909, 721, 15009.3),
        ('v5_1768235312', 89435.63603047856, 734, 12184.7),
        ('v5_1768235983', 98379.19963352643, 987, 9967.5)]

print(extract_key_performance_indicators(data))